The absolute lymphocyte count (ALC) at presentation has been associated with survival in various malignancies. However, its prognostic value in acute myeloid leukemia (AML) has not been established. In a series of 1702 newly diagnosed patients with AML, we evaluated the prognostic value of ALC at diagnosis with regard to induction chemotherapy response, disease-free survival (DFS) and overall survival (OS). Low initial ALC (< 1 × 10(9)/L) appeared as a poor prognostic factor for DFS (p = 0.01) and OS (p = 0.02), while higher ALC (> 4.5 × 10(9)/L) showed a lower response rate after one (p = 0.004) or two induction chemotherapy courses (p = 0.01). However, ALC did not appear as an independent predictor of outcome in a multivariate analysis model also including age, cytogenetics and white blood cell count. Examination of lymphocyte subsets is warranted to specify the relationship between ALC at diagnosis and clinical outcome in AML.